<!DOCTYPE html>
<html>
	<head>
		<meta charset="{CHARSET}">
		<title></title>
		<link style="text/css" rel="stylesheet" href="css/bootstrap.min.css" />
	</head>
	<body>
		<script type="text/javascript" src="jquery-3.4.1.min.js"></script>
		<script type="text/javascript" src="js/bootstrap.min.js"></script>
		<script type="text/javascript">
			$(function(){
				$("#btn1").click(function(){
					$("#res").addClass("btn btn-success");
				});
				
				$("#btn2").click(function(){
					$("#res").addClass("btn btn-danger");
				});
				
				$("#btn3").click(function(){
					$("#res").toggleClass("btn btn-success");
				});
				
				$("#btn4").click(function(){
					$("#res").removeClass("btn btn-success");
				});
				
				$("#div").css("border","solid 5px #f00").css("width","300px")
				.css("height","100px");
				
				alert($("#div").css("width"));
			})
		</script>
		<button id="btn1">成功</button><button id="btn2">失败</button>
		<button id="btn3">成功/失败</button><button id="btn4">删除</button>
		<hr>
		<button id="res">结果</button>
		<hr>
		
		<div id="div">样式添加结果</div>
	</body>
</html>
